package com.itheima.practise1;

public class MyStringBuilder {
    public static void main(String[] args) {
        method1();
        System.out.println("--------------");
        method2();
        System.out.println("----------------");
        method3();
        System.out.println("-----------------");
        String s1 = "ab";
        String s2 = "abc";
        String s3 = s1 + "c";
        System.out.println(s3 == s2);    // false
        System.out.println(s3.equals(s2));  // true

    }

    private static void method3() {
        String s1 = "a" + "b" + "c";
        String s2 = "abc";
        System.out.println(s1 == s2);   // false
        System.out.println(s1.equals(s2));   // true
    }

    private static void method2() {
        String s1 = "abc";
        String s2 = "abc";
        System.out.println(s1 == s2);    // false
        System.out.println(s1.equals(s2));  // true
    }

    private static void method1() {
        String s1 = new String("abc");
        String s2 = "abc";
        System.out.println(s1 == s2);   // false
        System.out.println(s1.equals(s2));  // true
    }
}
